I've just come across a post on another forum (AVForums.com) that claimed that the GTX 680 will downclock itself below 705 MHz if the GPU temperature exceeds 70ÂºC?

Now, I have come across a strange issue while overclocking my own GTX 680 using a non-Adaptive power profile and MSI Afterburner v2.2.0 beta 15 to set a 132% power limit, +150 MHz on the core clock and +350 MHz on the memory clock. Basically my card will happily run at up to 1,287 MHz on the core with 6.7 GHz memory in various games without any freezes, stutters, artifacts or errors to suggest I'm pushing it beyond its means. Temperatures with my custom fan profile, which increases the fan speed 1% for every 1ÂºC above 40ÂºC, haven't exceeded 75ÂºC, even when running stressful benchmarks such as 3DMark11 or Heaven 11 (DX11, 1920x1200, Extreme Tessellation, 8xAA/16xAF), and with many games max out at 72ÂºC (Alan Wake is the only one I've seen to top out at 75ÂºC).

Yet I came across an issue where the core clock appeared to 'stick' at 705 MHz even when I exited the game (I first noticed it the first Mass Effect after doing some overclocking benchmarks) and loaded another game. Between loads, the card correctly drops down to 2D speeds of 324 MHz on both the core and memory clocks. This 705 MHz core during gaming never wavered even though the GPU temperature was below 70ÂºC at the time. At first I thought it was possibly a bug with Afterburner, since that core clock has been reported erroneously by other software including GPU-Z (v0.6.0 fixes it), but I confirmed with other software that the default core was showing as 1,006 MHz but the reading during 3D games was locked at 705 MHz. The only way I was able to fix it was by restarting my PC. Several other people on the Guru3D.com forum have reported similar issues too and they fixed it by restarting their PCs.

So is this a safety/design feature built into the card or a bug? If the card really is designed to underclock itself above 70ÂºC as someone claims then isn't that a bit over-cautious considering that the operating temperatures of high-end cards are typically in the high 70sÂºC/low 80sÂºC with the default fan profiles. I read somewhere that the Kepler chips have a thermal shutdown temperature of 98ÂºC so I wouldn't expect throttling to kick in until the card was at 85ÂºC or something.

I've just come across a post on another forum (AVForums.com) that claimed that the GTX 680 will downclock itself below 705 MHz if the GPU temperature exceeds 70ÂºC?

Now, I have come across a strange issue while overclocking my own GTX 680 using a non-Adaptive power profile and MSI Afterburner v2.2.0 beta 15 to set a 132% power limit, +150 MHz on the core clock and +350 MHz on the memory clock. Basically my card will happily run at up to 1,287 MHz on the core with 6.7 GHz memory in various games without any freezes, stutters, artifacts or errors to suggest I'm pushing it beyond its means. Temperatures with my custom fan profile, which increases the fan speed 1% for every 1ÂºC above 40ÂºC, haven't exceeded 75ÂºC, even when running stressful benchmarks such as 3DMark11 or Heaven 11 (DX11, 1920x1200, Extreme Tessellation, 8xAA/16xAF), and with many games max out at 72ÂºC (Alan Wake is the only one I've seen to top out at 75ÂºC).

Yet I came across an issue where the core clock appeared to 'stick' at 705 MHz even when I exited the game (I first noticed it the first Mass Effect after doing some overclocking benchmarks) and loaded another game. Between loads, the card correctly drops down to 2D speeds of 324 MHz on both the core and memory clocks. This 705 MHz core during gaming never wavered even though the GPU temperature was below 70ÂºC at the time. At first I thought it was possibly a bug with Afterburner, since that core clock has been reported erroneously by other software including GPU-Z (v0.6.0 fixes it), but I confirmed with other software that the default core was showing as 1,006 MHz but the reading during 3D games was locked at 705 MHz. The only way I was able to fix it was by restarting my PC. Several other people on the Guru3D.com forum have reported similar issues too and they fixed it by restarting their PCs.

So is this a safety/design feature built into the card or a bug? If the card really is designed to underclock itself above 70ÂºC as someone claims then isn't that a bit over-cautious considering that the operating temperatures of high-end cards are typically in the high 70sÂºC/low 80sÂºC with the default fan profiles. I read somewhere that the Kepler chips have a thermal shutdown temperature of 98ÂºC so I wouldn't expect throttling to kick in until the card was at 85ÂºC or something.

Taken from the Guru3D.com GTX 680 overclocking article here: http://www.guru3d.com/article/geforce-gtx-680-overclock-guide/16

[i]"There is a downside though, sometimes the Dynamic boost feature went nuts on us and as protection clocked down the core frequency towards the 736 MHz range. Definitely a protection as only restarting the system would get the normal clocks back on their feet again. This happened to us only once though."[/i]

That sounds to me like exactly the same issue myself and others are seeing. Guru3D.com seem to consider it a bug so the question is can this be fixed through a driver update or does it require a new BIOS (since the GPU Boost is built into the hardware itself)?

Taken from the Guru3D.com GTX 680 overclocking article here: http://www.guru3d.com/article/geforce-gtx-680-overclock-guide/16

"There is a downside though, sometimes the Dynamic boost feature went nuts on us and as protection clocked down the core frequency towards the 736 MHz range. Definitely a protection as only restarting the system would get the normal clocks back on their feet again. This happened to us only once though."

That sounds to me like exactly the same issue myself and others are seeing. Guru3D.com seem to consider it a bug so the question is can this be fixed through a driver update or does it require a new BIOS (since the GPU Boost is built into the hardware itself)?

It goes in to protection mode when the clock speed goes over the power limit.

I looks like your making the mistake of thinking +150 adds on the mhz when its an offset. I had it set to +150 and was boosting on to 1310mhz causing the card to go in to protection mode.

The best way I have found to best OC this card is to start with offset on the clock at +100 and memory at +200 and then bench with 3DMark 11 then increase the offsets by +25 then bench again, keep doing that until your score starts dropping which will mean you have found the power limit then drop the offset back by -5 each time until the score goes back up again.

It goes in to protection mode when the clock speed goes over the power limit.

I looks like your making the mistake of thinking +150 adds on the mhz when its an offset. I had it set to +150 and was boosting on to 1310mhz causing the card to go in to protection mode.

The best way I have found to best OC this card is to start with offset on the clock at +100 and memory at +200 and then bench with 3DMark 11 then increase the offsets by +25 then bench again, keep doing that until your score starts dropping which will mean you have found the power limit then drop the offset back by -5 each time until the score goes back up again.

You don't have to restart your pc, to fix it, simple just close either MSI Afterburner or EVGA Precision X, whichever you're running, then reopen the software, you will see that the clock will start at 1006mhz again.

You don't have to restart your pc, to fix it, simple just close either MSI Afterburner or EVGA Precision X, whichever you're running, then reopen the software, you will see that the clock will start at 1006mhz again.

[quote name='jincuteguy' date='29 March 2012 - 07:53 AM' timestamp='1333003994' post='1389402']
You don't have to restart your pc, to fix it, simple just close either MSI Afterburner or EVGA Precision X, whichever you're running, then reopen the software, you will see that the clock will start at 1006mhz again.
[/quote]

Will do. Thanks for that tip. /thanks.gif' class='bbc_emoticon' alt=':thanks:' />

You don't have to restart your pc, to fix it, simple just close either MSI Afterburner or EVGA Precision X, whichever you're running, then reopen the software, you will see that the clock will start at 1006mhz again.

Will do. Thanks for that tip. /thanks.gif' class='bbc_emoticon' alt=':thanks:' />

[quote name='djmorgan' date='29 March 2012 - 10:41 AM' timestamp='1333014069' post='1389445']
Not happening here! I have been running Heaven DX11 3.0 for some time on and off and the temps have been getting into the low 80's but no throttling has occurred, I have the new 301 drivers.

The high temps have taken me a bit by surprise but so far have had no issues due to temps.
[/quote]

The default fan profile isn't terribly great IMO when overclocking although I've no doubt NVIDIA set it to balance out cooling and noise. That's why I've been using a custom fan profile which even with the fan at 75% is still a quiet hum, thanks to the fact my case stands on a carpet and anti-vibration pads! Highest temperatures I've seen at near 1,300 MHz on the GPU clock and 6.7 GHz on the memory is 75ÂºC. That's why I was surprised to hear about the card throttling itself at 70ÂºC. That seemed awfully low for a modern high-end graphics card with a shutdown temperature of two degrees short of 100ÂºC!

Not happening here! I have been running Heaven DX11 3.0 for some time on and off and the temps have been getting into the low 80's but no throttling has occurred, I have the new 301 drivers.

The high temps have taken me a bit by surprise but so far have had no issues due to temps.

The default fan profile isn't terribly great IMO when overclocking although I've no doubt NVIDIA set it to balance out cooling and noise. That's why I've been using a custom fan profile which even with the fan at 75% is still a quiet hum, thanks to the fact my case stands on a carpet and anti-vibration pads! Highest temperatures I've seen at near 1,300 MHz on the GPU clock and 6.7 GHz on the memory is 75ÂºC. That's why I was surprised to hear about the card throttling itself at 70ÂºC. That seemed awfully low for a modern high-end graphics card with a shutdown temperature of two degrees short of 100ÂºC!

I have noticed that the GPU boost does in fact start downclocking itself at 70c. While running Heaven 3.0 my cards will sit at 1215MHz constantly until the moment they hit 70c, then they start dropping down as low as 1189MHz. Even with the temperature as high as 85c they fluctuate between 1189-1215, so I'm not sure why they even begin to fluctuate in the first place. If the cards can still hit 1215 at 85c, why does it start downclocking at 70c?

I have noticed that the GPU boost does in fact start downclocking itself at 70c. While running Heaven 3.0 my cards will sit at 1215MHz constantly until the moment they hit 70c, then they start dropping down as low as 1189MHz. Even with the temperature as high as 85c they fluctuate between 1189-1215, so I'm not sure why they even begin to fluctuate in the first place. If the cards can still hit 1215 at 85c, why does it start downclocking at 70c?

[quote name='djmorgan' date='29 March 2012 - 10:41 AM' timestamp='1333014069' post='1389445']
Not happening here! I have been running Heaven DX11 3.0 for some time on and off and the temps have been getting into the low 80's but no throttling has occurred, I have the new 301 drivers.

The high temps have taken me a bit by surprise but so far have had no issues due to temps.
[/quote]

You can do this, once you're in your desktop, click Start -> Switch user. Once you're out at the login screen, log back in, and you will see the clock will be set to 705mhz or around there. And it won't go up even when you open a 3d game. So you either restart your PC or just restart MSI Afterburner or EVGA Precision X.

Not happening here! I have been running Heaven DX11 3.0 for some time on and off and the temps have been getting into the low 80's but no throttling has occurred, I have the new 301 drivers.

The high temps have taken me a bit by surprise but so far have had no issues due to temps.

You can do this, once you're in your desktop, click Start -> Switch user. Once you're out at the login screen, log back in, and you will see the clock will be set to 705mhz or around there. And it won't go up even when you open a 3d game. So you either restart your PC or just restart MSI Afterburner or EVGA Precision X.

[quote name='jincuteguy' date='30 March 2012 - 03:51 AM' timestamp='1333043505' post='1389588']
You can do this, once you're in your desktop, click Start -> Switch user. Once you're out at the login screen, log back in, and you will see the clock will be set to 705mhz or around there. And it won't go up even when you open a 3d game. So you either restart your PC or just restart MSI Afterburner or EVGA Precision X.
[/quote]

And why in the hell would I want to do that? I have set a fan profile now and all is real cool.

nVidia why don't you at least give us a fan profiler in the control panel?

You can do this, once you're in your desktop, click Start -> Switch user. Once you're out at the login screen, log back in, and you will see the clock will be set to 705mhz or around there. And it won't go up even when you open a 3d game. So you either restart your PC or just restart MSI Afterburner or EVGA Precision X.

And why in the hell would I want to do that? I have set a fan profile now and all is real cool.

nVidia why don't you at least give us a fan profiler in the control panel?

I have noticed that the GPU boost does in fact start downclocking itself at 70c. While running Heaven 3.0 my cards will sit at 1215MHz constantly until the moment they hit 70c, then they start dropping down as low as 1189MHz. Even with the temperature as high as 85c they fluctuate between 1189-1215, so I'm not sure why they even begin to fluctuate in the first place. If the cards can still hit 1215 at 85c, why does it start downclocking at 70c?
[/quote]

I have also noticed the same thing here. It doesn't throttle by much, but it makes benchmarking a lot harder.

I have noticed that the GPU boost does in fact start downclocking itself at 70c. While running Heaven 3.0 my cards will sit at 1215MHz constantly until the moment they hit 70c, then they start dropping down as low as 1189MHz. Even with the temperature as high as 85c they fluctuate between 1189-1215, so I'm not sure why they even begin to fluctuate in the first place. If the cards can still hit 1215 at 85c, why does it start downclocking at 70c?

I have also noticed the same thing here. It doesn't throttle by much, but it makes benchmarking a lot harder.

I have noticed that the Voltage drops to 1.162 at 70c and to 1.15 at 80c. Out of curiosity I let mine hit 92 to see if it would drop again, but it did not. I don't know when it drops again because I didn't want to let my temps get any higher.

I have noticed that the Voltage drops to 1.162 at 70c and to 1.15 at 80c. Out of curiosity I let mine hit 92 to see if it would drop again, but it did not. I don't know when it drops again because I didn't want to let my temps get any higher.

Yea I don't know who invented GPU Boost but it's not really a good feature, especially for a good card like gtx 680.

For anyone that running with Vsync on, you will never see the card run at the overclock clock that you set. It will always run at the default clock which is 1006mhz.
I know ppl will say oh why would overclock matter when you're running with Vsync since it cap your fps at 60. Well the issue is if you run games at 2560-1600 resolution,
and play intensive game such as BF3 or Metro 2033, that extra fps boost will either break it over 60fps or below it. And with this GPU boost feature, the card will always run at the default clock if you turned on Vsync.
You guys can test this out and check it.

Yea I don't know who invented GPU Boost but it's not really a good feature, especially for a good card like gtx 680.

For anyone that running with Vsync on, you will never see the card run at the overclock clock that you set. It will always run at the default clock which is 1006mhz.

I know ppl will say oh why would overclock matter when you're running with Vsync since it cap your fps at 60. Well the issue is if you run games at 2560-1600 resolution,

and play intensive game such as BF3 or Metro 2033, that extra fps boost will either break it over 60fps or below it. And with this GPU boost feature, the card will always run at the default clock if you turned on Vsync.